尝试打印(revision_id，depth，revno，end_of_merge)元组的迭代器时出错

Question

如果我输入代码：

b = Branch.open('directory containing repository')
r1 = 1010 #input revision number
r2 = r1-5 #last revision number that I want to sort to
r1 = b.dotted_revno_to_revision_id((r1,), _cache_reverse=False) #revision ids of r1 and r2
r2 = b.dotted_revno_to_revision_id((r2,), _cache_reverse=False)

test = b.iter_merge_sorted_revisions(start_revision_id=r1, stop_revision_id=r2, stop_rule='include', direction = 'reverse')

for i in test:
    print i[0]

iter_merge_sorted_revisions应该返回(revision_id，depth，revno，end_of_merge)元组的迭代器。

所以当我打印所有的i时，它应该返回给我r1和r2之间的所有revision_ids。

它确实会把它们返回给我，一直到r2。但我一直收到一个错误，一旦for循环结束，我的其余代码就会停止运行。

错误码如下：

Traceback (most recent call last):
File "log.py", line 60, in <module>
for i in revisions:
File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 634, in _filter_start_non_ancestors
pmap = self.repository.get_parent_map([rev_id])
File "/usr/lib/python2.7/dist-packages/bzrlib/vf_repository.py", line 1882, in get_parent_map
self.revisions.get_parent_map(query_keys).iteritems():
File "/usr/lib/python2.7/dist-packages/bzrlib/groupcompress.py", line 1356, in get_parent_map
return self._get_parent_map_with_sources(keys)[0]
File "/usr/lib/python2.7/dist-packages/bzrlib/groupcompress.py", line 1375, in _get_parent_map_with_sources
new_result = source.get_parent_map(missing)
File "/usr/lib/python2.7/dist-packages/bzrlib/groupcompress.py", line 2093, in get_parent_map
self._check_read()
File "/usr/lib/python2.7/dist-packages/bzrlib/groupcompress.py", line 2051, in _check_read
raise errors.ObjectNotLocked(self)
bzrlib.errors.ObjectNotLocked: <bzrlib.groupcompress._GCGraphIndex object at 0x7fd55e846390> is not locked

我不知道出了什么问题，因为for循环已经完成，因为它确实返回了我想要的最后一个版本。我不知道我是否需要以某种方式手动结束循环，但任何想法都很感谢！

Answer 1

您需要对分支进行读锁定，然后才能访问它：

b.lock_read()
try:
    test = b.iter_merge_sorted_revisions(start_revision_id=r1, stop_revision_id=r2, stop_rule='include', direction = 'reverse')
finally:
    b.unlock()